Joe Thornton had just one fight all of last season, against the Kings’ Drew Doughty on April 5. The fight with Toews was just his second in the last four seasons. (USA TODAY IMAGES)

CHICAGO - Even though they have a few fights on their resumes, seeing Sharks and Blackhawks captains Joe Thornton and Jonathan Toews fight one another in the first period on Friday night in Chicago was unexpected. It started, seemingly, when Toews hit Thornton from behind, earning a boarding minor. Moments later, at 15:31, the pair dropped the gloves and went at it. Neither landed any damaging blows.

After the game, Toews gave the impression that Thornton had been irritating him for some time now.

“The last few games, including last season…always some stuff going on, be it after the whistles or during the play,” Toews said. “I guess it just comes down to players trying to get under your skin and test you a little bit. I figured at some point I had to stand up for myself.”

Thornton was surprised when Toews asked him to go.

“Johnny just asked me to fight, and I was kind of shocked,” Thornton said. “I said ‘sure.’ That’s how it went. He just hit me from behind, it wasn’t anything serious. He just asked me to fight, and I obliged.”

Thornton denied that he was trying to spark his team, which went on to lose its seventh straight game (0-4-3).

Along with the fighting major and boarding minor, Toews was called for an unsportsmanlike conduct minor, too, giving the Sharks a four-minute power play. They failed to capitalize against Chicago’s penalty kill, ranked second in the league. Dave Bolland gave Chicago the 1-0 edge at 19:16 after Patrick Marleau’s interference penalty nullified the Sharks’ power play.

“That’s the unfortunate thing to come out with four minutes in penalties, but obviously guys did a great job,” Toews said.

Thornton had just one fight all of last season, against the Kings’ Drew Doughty on April 5. The fight with Toews was just his second in the last four seasons, according to Hockeyfights.com. It was the third of Toews’ career, and first since a bout with St. Louis’ David Backes on Jan. 2, 2010.

“I did it, and glad I did it. I think it helped our team. Got the win. That’s the most important thing,” Toews said of Chicago's 4-1 victory.